


Backbone

by perniciousLizard



Series: Fired Up and Bone Weary [26]
Category: Undertale (Video Game)
Genre: M/M, Major Illness, Old Age, Sickfic
Language: English
Status: Completed
Published: 2016-12-21
Updated: 2016-12-21
Packaged: 2018-09-10 19:13:45
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,086
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8930461
Author URL: https://archiveofourown.org/users/perniciousLizard/pseuds/perniciousLizard
Summary: It’s nice getting a chance to grow older, but there are consequences to that, too.





	

**Author's Note:**

> Content Note: Lots of talk about diets, and poor diets.
> 
> Author Note: There is stuff that was intended to come in between the previous fic and this one, but it had been twenty minutes since I'd written someone getting sick and I couldn't take it anymore, so I hope you enjoy this little skip in time.

Sans hadn’t been sure about the new place, but when he got to walk outside and see the stars, it was tough missing the city.  The kids had a whole yard and Papyrus had always liked to be out in the fresh air.  They’d missed living in a smaller town, it’d turned out. It was better for everyone.

The slower pace suited Grillby more than anyone.  He wanted to be a part of “building a community.”  Sans wasn’t sure what that meant, really, but it sounded pretty cool.  

–

Sans’ bones ached, some nights.  A lifetime of poor health and worse choices was going to catch up with him, eventually.  Papyrus kept trying to drag him out to go jogging with him, like that didn’t sound like a fate worse than death to Sans.  Papyrus, at least, seemed as healthy as ever. The kids grew slower than other kids, but they’d never stop.  One day they were going to outgrow Sans, and he wasn’t sure how he felt about that.  

Grillby was looking thin.  There was less fire to him.  He seemed a little young for such a big change, but Sans was probably too young for aching joints.  What did he know?

It’s not like Grillby wasn’t eating.  He had the same enormous appetite he always had.  Sans only stole enough of his food to not be suspicious.  

“You don’t seem hungry lately.”  Of course Grillby was always aware of everything Sans ate.  He radiated concern.  

“uh.  that right?”  Sans asked.  

“I hope your brother isn’t pressuring you into dieting,” Grillby said.  

“what.”

“He may act like he knows everything about nutrition, but if you’re really worried, you should trust a doctor over him.  I know he _means_ well, but I don’t trust wherever he gets his information.”  

“oh my god.”

“……what?”

“i stopped stealing your food ‘cause you’re looking thin.  but i want to hear more of this.”  

“What?” He held up his own hand and examined it.  "…huh."  

"what’s that about?” he asked.  Sans had not planned on bringing up the subject, but if they were on it, he might as well go ahead.

He shrugged.  

“last time that happened you were pretty stressed out.”

He shook his head. “I’m fine?”

“okay.”  

“I guess I haven’t been paying attention.”  

“okay?”

“And…I’ll do that,” he said, embarrassed.  

Sans nodded.  "good talk."

He didn’t notice any improvement, even if Grillby said he was "paying attention.”  Grillby started getting headaches, out of nowhere.  

“hey, guess what,” Sans said.

Grillby was laying, stretched out, on the couch.  He hadn’t been able to sleep, so he had decided to wait out the headache in the living room.  Sans didn’t feel like standing, so he sat on his legs.  

“…what?” His glasses were on the coffee table, so he sat up a little like he was trying to make out what Sans was doing.  

“no, you’ve gotta guess,” Sans said.  

“I don’t feel like doing this.”

“guess what time it is.”

“……”

“'bout time for you to see a doctor about what’s going on, here,” Sans said.  

“………maybe.”

“maybe?”

“Fine.” He tried to shake Sans off his legs.  

He set up an appointment for his next day off.  Sans had been hoping he’d take it a little more seriously and set it up for the next day, but he wasn’t going to push it more.  He had already pushed it, and gotten _something_ , so he was just going to have to put up with what he got.  

The headaches went away, mostly, in the next few days.  Sans was worried he’d cancel, but Grillby said he would still go since it was bothering Sans so much.  He’d made Sans go to the doctor plenty of times over the years, so it was only fair.  

–

Sans was in the kitchen, microwaving a burrito, when he heard the front door open. It was a little early for Grillby, but not _strangely_ early.  He hoped he’d still make dinner for him, despite the burrito.  

“heeey…oh boy,” Sans stopped short once he got a good look at Grillby.

He was a mess.  He came home sometimes with stains on his clothes or his tie already off, but it wasn’t that kind of mess.  The way he burned was sloppy and haphazard, like when he was tired.  

“headache back?” Sans asked.  

“…a little, but…”  He sat down on the couch, heavy.  "……I feel…dizzy…"

"uh.” Sans rubbed his skull.  "why the hell didn’t you close up early?“  

"…I was fine, until…"

"or call me. seriously.”  

“…I…didn’t think of it…my head is…”

“ok.”  Now was not the time to really get into it.  

Grillby fumbled with his tie, and Sans thought it might be tight, so he took it off for him.  

“hate to say it, but i don’t think we’re waiting until the day you set up,” Sans said.  He undid the top few buttons on his shirt, too, but it didn’t seem to help.  Grillby lay back on the couch.  Sans noticed that where he’d been looked a little singed.  The very end of his sleeves were turning black.  That sure wasn’t normal.  

Sans got out his phone.  He didn’t think Grillby could actually call the doctor himself, at the moment.  

“it got worse pretty sudden,” Sans explained, once introductions were out of the way.  "no idea what’s going on.  yeah."

He turned back towards the couch.  "uh…he’s kind of…losing shape really fast.”  His voice was shaking.  "…really not sure what to do here."

Grillby was getting smaller, too.  Oh, god.  Sans didn’t know what was causing this, or what to do, but he knew what it _was_.  He was dying.  Right there, and Sans was just going to _watch_.  

The doctor kept talking.  Sans had woken them up, but being woken up in the middle of the night was part of the job in such a small town.  

"what.  oh. yeah, i can do that.”

“I’ll be there as soon as I can,” the doctor said, and hung up.  

Sans looked around. He needed something sturdy and flammable to keep Grillby going until the doc got there.  He could see through the door into the dining room and he got a good look at Grillby’s fancy, expensive,  _wood_ dining room set.  Welp.

Grillby could be pissed about him ruining it if he was, you know, still alive.  Sans hadn’t married the dining room set, so if it was one or the other, the set was what was going to have to go.  

–

“He’s stabilized.”  The doctor was exhausted.  Sans was pretty sure they were wearing pajamas under their scrubs.  

“ok.”  Sans was suddenly wobbly.  Papyrus led him over to a chair and set him down in it.  "ok,“ he repeated.  "what the hell?”  

“His form destabilized because of a combination of poor diet and, most likely, family history,” the doctor said, calm.  

“HE DID LOSE SOME WEIGHT RECENTLY.  OR.  FIRE?”  Papyrus said.  

“don’t think his diet changed at all,” Sans said.  

“Yes, and that was probably the problem.  When he was younger, it would be easier for his form to compensate for poor diet.”

“what does that mean?”  He wasn’t getting enough, right?  But he ate a _ton_.

“He probably gets enough energy, but not the kind he needs, since he doesn’t live around other fire elementals.  He eats what everyone else does.  It’s a common problem when we are isolated from similar types of monsters.”

“OH, LIKE HOW SANS NEVER DRINKS ENOUGH MILK,” Papyrus said.  

“Yes.”

Sans didn’t care about that.  "so if he fixes that, he’ll be ok."

"It’s very important that he fixes that.  We were lucky that you were there.”

Sans felt sick.  

“He _might_ have stabilized on his own.”

“ok.”

“DOCTOR, I BELIEVE THAT SANS ALREADY FULLY COMPREHENDS THE SERIOUSNESS OF THE SITUATION,” Papyrus said.  

They nodded.  "Then you can make it clear to him, too."  They came over and put their hand on Sans’ shoulder.  He looked up at them.  "It’s lucky it happened this way, when he was still fairly young, and with you there.  Think of this as a warning.”

“sure.”  Sans was only partially absorbing what was being said to him.  He thought it was good his brother had been able to get a neighbor to come over and watch his kids, so at least someone was there with him and paying attention.  

–

Papyrus had to go home, to make sure the kids didn’t wake up with no one there to explain that Grillby was going to be fine.  Sans dozed, uneasy, in a chair in the waiting room until a nurse told him Grillby was stable enough for him to go in.  

“He’s woken up once,” the nurse explained, leading Sans in, “If he wakes up again, it would be better for him if there was a friendly face.”

“can’t get friendlier than mine,” Sans said.  That was just how his face was.

Grillby was sleeping, loosely formed, on a plain white hospital bed.  He looked frail, and Sans was not entirely prepared for how small he was.  

“It’s easier for his soul to keep his form stable at this size, until he recovers,” the nurse explained.

“okay.”  

The nurse brought a chair over for him, and then went back to his own work.  

“what the hell, grillbz,” Sans said, quiet.  

Grillby crackled gently.  He didn’t react.  

“hey, nurse, will grillbz be able to play the trombone after he gets better?” Sans asked.  

“I don’t see why not.”  

“that’s pretty cool.  he never could before.”  

Grillby continued to burn, otherwise silent.  It was tough to look at him, like this, but Sans’ skull was still partially back there watching him shrink away on the couch.  Seeing him sick, but stable, made the tightness behind his eyes start to loosen.  

He sniffed.  "you’re pretty quiet, grillbz, but i know you’re laughing on the inside.  you’ve just always gotta be the critic."

Sans tried a few more jokes.  He thought Grillby looked like he was a little more awake, even if he wasn’t responding.  

Grillby moved his hand.  Sans patted at it, awkward.  

"…I’m sick," Grillby said.  Sans had to lean in to hear him, and he was pretty sure the nurse wasn’t getting any of it.  "…why am I…being…punished…."

" _pun_ ished," Sans repeated.  "the next time i almost die i hope i think up that great a line.”  His nose was running.  He went to wipe his nose with his sleeve and realized he was crying.  Well.  He probably shouldn’t be surprised.  

“…Sans?”

“yeah, buddy?”

“…sorry.”

“eh, you didn’t do it on purpose.”  

Grillby tried to push himself into a sitting position.  The nurse hurried over and helped him up.  "……glasses?"  He was looking around for them.  

"uh.  his glasses around here?”  

The nurse nodded and went to get them.  Most of the time no one understanding what Grillby said was just kind of annoying, but this could get pretty bad.  

The nurse handed Grillby his glasses, and Grillby put them on, then took them off again and looked at them, up close.  

“what’s up?” Sans asked.  

“If you have trouble seeing now, that will most likely correct itself in a week or so,” the nurse said.

“…no.  I just…”  He put the glasses back on.  "I hadn’t realized…how small…"  They looked oversized on his face.  He held up his hand and examined it, flickering with worry.  

Sans reached over and wrapped his fingers around Grillby’s wrist.  "heh.”

“…I’m smaller than _you_?”  He was genuinely distressed.  

“it’s not permanent, babe, so you can hold off on the divorce.”  

He stared at Sans, blank.  

The nurse came back over.  "If you’re going to be awake for a while, eat some of this."  He set a tray down.  That distracted Grillby from whatever was going on in his head.  He stared at the tray, instead of Sans.  

"uh.  you’re still probably pretty tired,” Sans said.  "not hungry?"

"…I’ve never been more hungry in my life," he said, very slow.  "…I was told what happened, but…"

"some kinda vitamin deficiency, i guess,” Sans said.  

“………right. I don’t remember…”  He picked something up off the tray.  "I was at the bar."

"you got home and were kind of messed up, so i called the doc.”

“I was…very dizzy?”  

“yeah.”  

Grillby started to say something.  

“yeah?”

He gestured for Sans to lean in a little closer.  

“what’s up?”

He touched Sans’ cheekbone, and there was a slight hissing sound.  

“must’ve been something in my eyesocket, there,” Sans said.  He winked.  

“……” Grillby stared at him for little longer, and then turned back to his tray.  

“you’re, uh, supposed to be eating that.  pretty sure.”  

“…could you…look away?”  

Sans shrugged and got a good look at the ceiling fan.    

A few seconds later, Grillby said, “okay.”  

The tray was empty.

“okay.  you ever think about entering a contest?”

His face was tinged with blue.  "……sorry.“  

"nah, come on. i mean.  i do feel like i missed out on something special.  but i can watch you horf down lots of food at once some other time.”  

“Not that.” He looked irritated, which Sans considered a win.  "…you know what I mean."

"i gotta apologize, too.”

“No you don’t.”

“yeah.  uh.  you remember your dining room?”  

“…do I…”

“how you used to have this table and some chairs in there?”  

Grillby rubbed under his oversized glasses.  "…tell me later."

"break it to you lightly, right.  unlike what i did to that table.”  

“…I think I’m going to pass out.”  

“look, i said i’m sorry.”  

He was changing colors.  

“oh.  you meant, like, actually.  uh…”  Sans waved the nurse over.  He helped Grillby back down into a more comfortable position.  "it’d be kind of great if someone other than me in this place understood a word he said," Sans said.  "i appreciate what you guys are doing, really, but, uh.”  He didn’t really feel like he could leave.  Not that he wanted to, but Papyrus was probably going to show up later and try to get him to do something other than just sit around and wait.  

“The doctor understands him pretty well,” he said.  "But they’re asleep in the break room right now."

"oh, right.” He probably couldn’t expect to wake someone up in the middle of the night and have 'em keep going forever.  

Sans watched Grillby rest until the quiet lulled him into his own uncomfortable sleep.  

–

The first time Grillby was steady enough to stand, his glasses were aimed straight at Sans’ nose hole.  He was still technically taller, thanks to his candle flame-like head, but Sans was pretty sure that if he’d had hair, they would’ve been about even.  

Grillby had a death-grip on Sans’ shoulder until he was sure he wasn’t going to suddenly get dizzy and tip over.  

Sans kept his hand lightly on his back.  "okay?"

He nodded.  

"not so bad, right?”

Grillby looked him over.  "……horrible."

Sans snorted.  He knocked their foreheads together.  "oh well.  it’s not forever, anyway.”  He closed his eyes and felt Grillby kiss him.

He sighed.  "I want to go home."

"yeah.”  

Grillby dropped his head on Sans’ shoulder.  "…I’m a mess."

"yeah.  it’s ok, though.”  He rubbed Grillby’s back.  

He twitched, laughing.  "…you say: 'no you aren’t.’"

"oops.”  

“…I’d better sit down.”  

Sans settled him back on the bed.  Grillby patted the space next to him, and Sans climbed on, too.  Grillby was well enough that they had long stretches of time with just the two of them.  Grillby shifted over, picked up Sans’ arm, and tucked himself in.  

“if you wanted to cuddle, you coulda just asked,” Sans said.  "skeletons are known for being warm and huggable, after all."

"…shhhh."

"ok, ok.”  He tucked Grillby’s head under his chin.  He knew he was one of the few familiar things Grillby got to have until he went home. “whatever you want." 

–

Papyrus had cleared the mess out of the dining room.  It was the first room Grillby headed to, when he got to go home, and Sans was relieved to find the room empty.  He didn’t really want Grillby to get a nice visual of how much Sans had kind of freaked out back there.  Papyrus had even repaired the window.  Sans had the best brother, no question.  

Grillby looked around the empty dining room.  

"that one was kind of ugly, anyway,” Sans said.  Maybe if he annoyed Grillby enough, he’d let it go.

He hadn’t been talking much, at all.  He turned his attention to Sans, slipping his arm around Sans’ waist.  

“let’s get out of here.”  

Grillby kissed his cheek and nodded.  

“they might as well call you clingby lately,” Sans said.  

His plan to annoy Grillby kept failing, catastrophically.  He was just too happy to be home.  He shrugged.  

“not that i’m complaining.”  

The scorch marks and the big holes in the fabric of the couch were gone.  His brother had somehow managed to reupholster it while they were gone.  He must’ve paid someone, unless he’d picked up a new hobby Sans didn’t know about.  Grillby touched the back of the couch and shook his head.  He walked into their bedroom.  Sans trailed after.  

Grillby went over to his closet and took out one of his shirts.  He held it up to himself.

“it’ll just be a little loose for a while.  or you can grab something from me.”

He shook his head and opened up the drawer where Sans kept his t-shirts when they weren’t on the floor.  He pulled out one that said “I’m With Stupid” and held it up.

“that’ll look great on you.”

He seemed to take that as a challenge.  He pulled off the shirt he had on – Papyrus had brought over all the clothes he’d bought undersized because they showed off his muscles, and that was mostly what Grillby had been wearing – and put on Sans’ t-shirt.  He noted where the arrow was pointing and stood next to Sans.  

“hey.”  

It fit, though. Grillby went back over to the dresser and sorted out the shirts he hated the least.  Sans owned three and a half pairs of pants, so that search mostly failed until Grillby found the pair of gray sweatpants that Sans had forgotten about and had barely ever worn.  It had fewer stains than his other sweatpants.  Grillby put them on, resigned, and sat on the bed.  

“i know it’s just, uh, how you are sometimes, pal,” Sans said, sitting next to him, “but not talking at all is kind’ve, uh, making this a little weird.”  

He nodded and rested his head on Sans’ shoulder.  

“okay.”

“………sorry.”

It was a relief to hear even that much.  "don’t worry about it."  After a little while: "that shirt’s still pointing at me.”

“…don’t buy shirts like that if you can’t handle them.”  

“my own weapon turned against me.  grillbz.  i thought i could trust you.  'cause you were way too big and classy to ever wear it.”  

“You said it looked great on me.”  

“sure.  i mean. you look hot in it.”  

“Thank you.”  He slowly took a deep breath.  "…have I been…clingy?"

"yep.  that’s ok.”  That was kind of a delayed reaction to that joke he made earlier.  Sans really wondered what was going on in Grillby’s head.  

He nodded.  

“i mean, that’s what i’m here for, right?  it’s sort of my job.”  

“…what is?”

Sans shrugged. “being around to lean on, i guess.”  

“……you should be…angrier with me.”

“heh.  what?” He was genuinely confused.  

“I did this to myself.  Right?  I was careful, but it was inconvenient, so I forgot and nothing terrible happened, so I stopped bothering.”

“so you knew something like this could happen?”

“I’ve had relatives not recover from this,” he said.  "I knew."

"grillbz.  i can’t tear into you for that.  it sounds like something i’d do.”

“Still.”  

“i dunno.  here’s how i see it.  we’re not getting younger, either of us, so one day something like this is happening and one of us isn’t getting better.  i’d feel like dirt i pitched a fit and that was the last thing you got from me.”  

“………morbid.”

“i’ve got _no_ idea why i’d be thinking about that stuff lately.  i kind of figured i’d go first, but maybe that’s not how it’ll work.”  

“Well.  It’s true neither of us is a boss monster.”  He shook his head.  "I can’t believe I ate my dining room set."  He moved away and stretched.  

"well.  you didn’t get that much of it.  doc showed up pretty quick.”

“There’s none of it left.”

“i kind’ve used a, uh, wide attack to smash it.”  He didn’t want Grillby feeling bad about the table.  That was really all on him.  He probably didn’t even have to destroy any of it, since it took the doctor five minutes to get there.

“…well, I don’t mind buying a new one.”  

“you kept trying to eat the couch, but whatever they coat those with is pretty effective,” Sans said.  

“…I…see…”

“you know, paps has been chopping up firewood and has a pile of it in the back of the house?  i sure didn’t know that.”  

Grillby laughed.  Sans hadn’t intended to tell him any of that, but if he thought it was funny, it couldn’t have been that bad an idea.  

“so.  you’re tired?”  They had just been sitting on the bed for a while.  

“…the opposite.  I haven’t had this much energy in… _years_.”  He stood up and stretched, again.

Was that just the buildup of energy before he went back to normal, or had he just been sick that long with no one noticing?  Well, no point worrying about it now.  "uhoh."

”…what?“

"you aren’t gonna want to start doing stuff again, are you?  remember when you kept trying to get me to go dancing with you?  hoo boy.”

“I remember,” Grillby said, dark.  "You know, I think that’s what I feel like doing."

"what?  you’re still sick.”

“I’m out of that tiny room, I’m alive, and I can eat real food again.  I want to celebrate.”  

“maybe you should do some of that.  eat some real food.”

“I will.”  He held out his hand.  

Sans sighed and stood up.  "there’s no music."

Grillby quickly remedied that.  

"guess you got me.”  He shrugged.  He actually didn’t mind.  It was nice seeing Grillby’s mood pick up.  

“Yes.”  

Sans took his hand and Grillby pulled him against his chest.  

“ok.  i thought i was used to it, but _this_ is weird.”  It wasn’t normal to look Grillby in the glasses when he got needled into doing this.  He wasn’t straining anything to look at him.  

Grillby was never going to get more than a slow dance out of him, but shuffling around at eye level was actually pretty nice.  He could read Grillby’s expression and how happy he was right then, with Sans, listening to cheesy jazz and waiting for a good moment to sneak in a kiss.  

There were a couple things Sans was going to miss, when everything went back to normal.  He wasn’t going to say that out loud.  Grillby was only the way he was because he’d been so sick.  

When Grillby _did_ return to normal – in a sudden burst, destroying one of Sans’ favorite shirts – not everything else went back to normal with him.  Sans stopped being so agreeable about getting hauled around in time to music, but there were definite differences.  For a long, long time afterward, when Grillby got into bed, he would curl himself up against Sans’ chest and draw his legs up so they didn’t reach all the way to the end of the bed.  If Sans woke up, he would wrap his arms around him and hold onto him.  They didn’t usually stay that way, but that was how they always started.

Eventually, Sans’ back took a turn for the worse, and for a while he had only a few specific ways he could sleep until it got better.  They had to switch things up.  Even when Sans recovered, they would shift around more than they had, but they still tended towards what was, by that point, an old routine.

Grillby wanted to know Sans was there for him, and Sans could say he was forever, but physical things like that were what sunk in and stayed with him.  

Sans didn’t mind. He liked that someone wanted him there to lean on.  


End file.
